It happens routinely that people drive past David Borman's small house on the Braden River, smash the brakes and photograph something they can't readily define. What is it? A spaceship? Submarine? Speedboat? What?

Cheryl Kirkhoff happened upon the house in her Busy Bee Lawn Service truck when she stopped in the middle of the street and gawked as if seeing spectacular holiday lights.

Her granddaughters Trinity Russell, 9, and Paige Russell, 8, were in the back seat, eyes wide, mouths agape and imaginations churning.

"Looks like some sort of water plane," Kirkhoff said. "Yeah, a water plane. That's exactly what it is."

"Can I ride it?" Trinity asked Borman.

"One day I hope so," Borman said. "This is my prototype for what will be an airliner for the ocean."

"Will you build me one?" Trinity asked.

"If you've got $3 million," Borman said.

It is part boat, part airplane and it is called "The Sea Phantom."

The 53-year-old Borman spent 17 years of his life dreaming, designing and building by hand what he thinks — no, what he knows — will globally revolutionize water transportation.

He lost a home, car, wife, $1 million and nearly an arm pursuing what he built in a Fort Myers gravel pit between two rusty shipping containers.

But if he could just get one person to pay $3 million for his 54-foot invention, if he could just show corporations, militaries and governments around the world what it is capable of doing, it would be worth all those times he rode his bike to the filling station with a gas can hanging from his neck so he could fuel his generator and continue working through the night.

"I think of Noah from the Bible," Borman said. "Supposedly he spent 100 years working on his boat and people called him nuts. I was called to do this. This is my life's calling. It's not a burden."

Sea Phantom

Because he hasn't found a buyer, what he basically has is the world's most expensive lawn ornament.

It's propped up by cinderblocks and Styrofoam under a live oak tree, near a swing, and it might as well be a 25-cent ride for kids at a strip mall. It can't go anywhere.

"It's like a hillbilly yard," Borman said. "Drive up and down this neighborhood enough and you'll see cars in the same shape. I just happen to have a million-dollar boat sitting in my front yard."

The model Borman has in his front yard is a 30-footer that was completed in 2006 and ran about 50 times in the Gulf.

It no longer runs, and Borman does not have the money to fix the parts to make it operable. But he's supremely confident in his idea and is working on scale for a 54-footer he hopes to sell.

"What I need more than anything is for somebody to order one and then this becomes the production prototype," Borman said. "I know what I've got. It's a matter of someone else realizing it."

The "Sea Phantom" is supposed to work like this: When the vessel hits 40 mph, foils underneath are forced down by hydraulics. This action raises the nose 12 feet above the average wave crest.

At 85 mph, only 2.5 square feet of the boat's surface area is in the water, according to Borman.

And since water is 800 times denser than air, the vessel is capable of traveling at speeds up to 150 mph using highly fuel-efficient engines.

Borman said his design can be up to 90 percent cheaper than an aircraft. The $3 million "Sea Phantom" can achieve what a $28 million helicopter can achieve and it burns half the fuel, Borman said.

"The 'Sea Phantom' fills a transport-technology gap between 50 mph and 150 mph on the water," he said. "You had slow but cheap ships and fast but expensive aircraft, and until now there's been nothing in between."

A flying boat

Borman said there are 40 distinct markets for his creation, including military, civilian commercial and civilian pleasure.

A 54-footer can carry between 18-20 people, he said.

From package delivery to ambulance service to thwarting pirate attacks on the high seas, Borman said the uses are many. A company was even interested in one to shuttle bananas up the California coast because the product could be on the shelves one day quicker.

Borman said he could get from Bradenton to Cancun, Mexico, in three hours, setting a world record in the process, and reach the Keys in under three hours. A trip to Tampa Bay could be completed in 15 minutes.

"It's too heavy to fly but in a marine environment it's the most amazing powerboat on the planet," Borman said.

There are critics on Internet message boards who say Borman's basic designs have been around for decades, but he insists he did not steal any ideas.

"No," Borman said. "I just put it together in a whole way that no one had ever thought of before. Well, 98 percent of the attempts to make high-speed travel over water practical have been aerospace engineers trying to make an airplane stay on the ground instead of a boat builder making a boat fly."

Borman's mother was a concert pianist in Chicago who died when he was young, he said. His father worked for the Navy in Virginia Beach, fixing F-4 Phantom fighter jets.

Borman watched his father work, and said he also spent a lot of time playing in the fighter jet junkyard, where some of the ideas for the "Sea Phantom" were formed.

Included in the entire process were three years of research, three years of model building and testing and three years of construction.

"Nobody would help me," he said. "They all thought I was nuts. I had to maintain a nine-year level of faith to keep it going despite incredible odds.

"I didn't even know what it was going to look like when I started."

What is it?

Between designing and building high-end racing boats and working on his "Sea Phantom" endeavor, Borman said he worked 16 to 20 hours a day for years.

He said his heart stopped once, and when he cut his arm to the bone with a power tool, he wrapped a belt around the wound, clutched the belt in his teeth and drove his five-speed Mazda to the hospital. He was back working 10 days later.

He said he was making good money in his boat design day job, but when the economy crashed the boating industry particularly suffered.

He borrowed against his house, but eventually lost that, and was living in a van for a while. He was also riding his bike 14 miles round trip to the "Sea Phantom."

He said his wife of 12 years left him.

"She couldn't take the stress anymore and I don't blame her," Borman said. "It was huge. I mean, this was a one-way trip for me. Either I was going to get this done and get an order or I was going belly up."

His new wife, Terri, admires what he has done, what he has created in thousands and thousands of work hours with his own hands. She admires his dogged determination.

"He has an incredible belief and he believes this is what he was supposed to do and he had to do it," she said.

Terri Borman said people knock on her door at least twice a week to inquire about the "Sea Phantom" and sometimes it can be a distraction.

"Most of the time people don't know what to think because they've never seen anything like it," David Borman said. "They just want to know what it is.

"At least half of the people who stop are virtually speechless, and then their next question is 'What is it?'"

So, what is it?

Is it an idea that could revolutionize water travel?

Or is it the world's most expensive lawn ornament?

Considering the complexity of the question, Borman is asked if he considers himself a sort of mad genius.

He smiles.

"Put it this way, no one on planet Earth is as good as I am at building these things," he said.